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Need some help with the connections of the potentiometer.

In the circuit example provided in the link, I'm connecting the potentiometer as a voltage divider and not a variable resistor right? So instead of just connecting 2 pins, the Vcc pin of the potentiometer is connected to pin 16 of the sg3525 chip, Gnd pin of the potentiometer to Gnd and the middle pin or output is connected to pin 2 of the sg3525 chip? Am I right about this?

Thanks.

enter image description here https://i.sstatic.net/bQ6Ta.jpg

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    \$\begingroup\$ yes... you are correct for the left pot. The other one is connected as a variable resistor. We don't tend to call pot pins Vcc and ground though... Usually just "one end", and the "other end", and of course the "wiper". \$\endgroup\$
    – Trevor_G
    Commented Aug 30, 2017 at 17:08
  • \$\begingroup\$ Yes Duty cycle wiper goes from 0 to pin 16 Vref=5.1, but as shown in datasheet they add series R's to reduce control range to 27% to 45% for choosing a suitable range. \$\endgroup\$
    – D.A.S.
    Commented Aug 30, 2017 at 17:26
  • \$\begingroup\$ @TonyStewart.EEsince'75 Wiper from 0 to pin 16, I think you meant "one end" of the pot to pin 16 as mentioned by Trevor? Thanks though! I'll try it out when I'm in the lab again. \$\endgroup\$
    – Morde
    Commented Aug 30, 2017 at 18:02

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That is correct in the case of the pot whose wiper is connected to pin 2 of the chip.

enter image description here

Figure 1. Standard potentiometer pinout. Source: Electronics Tutorials.

The second pot in your schematic has pins 2 and 3 connected together to make a variable resistor or "rheostat".

Some schematics will show a dot at one end of the pot indicating the clockwise end.

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  • \$\begingroup\$ Also Bournes standardized pin numbers as CW means tap goes from pin 1 to 3 \$\endgroup\$
    – D.A.S.
    Commented Aug 30, 2017 at 17:20
  • \$\begingroup\$ It is useful to explain why "pins 2 and 3 are connected together to make a variable resistor or rheostat". \$\endgroup\$
    – Circuit fantasist
    Commented Dec 19, 2019 at 22:02

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